Unruly Catapult

Defender
{T}: Unruly Catapult deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap Unruly Catapult.

Getting

Lightning Strike

Lightning Strike deals 3 damage to any target.

Voldaren Epicure

When Voldaren Epicure enters, it deals 1 damage to each opponent. Create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Goblin Javelineer

Haste
Whenever Goblin Javelineer becomes blocked, it deals 1 damage to target creature blocking it.

Clockwork Percussionist

Haste
When Clockwork Percussionist dies, exile the top card of your library. You may play it until the end of your next turn.

Cavalcade of Calamity

Whenever a creature you control with power 1 or less attacks, Cavalcade of Calamity deals 1 damage to the player or planeswalker that creature is attacking.

Shock

Searing Blood

Searing Blood deals 2 damage to target creature. When that creature dies this turn, Searing Blood deals 3 damage to the creature's controller.

Risk Factor

Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Mountain

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Chandra's Spitfire

Flying
Whenever an opponent is dealt noncombat damage, Chandra's Spitfire gets +3/+0 until end of turn.